§ 29. Watershed conservation easements and watershed agricultural easements. Restriction on alienation. A watershed conservation easement or watershed agricultural easement held by the city of New York shall not be transferred or conveyed by the city of New York unless the written consent of the record owner of the real property burdened by such easement is affixed to the instrument transferring or conveying such easement. For purposes of this section, the terms "watershed conservation easement" and "watershed agricultural easement" shall have the same meanings as defined in § 583 of the real property tax law.